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Soft starters were introduced to the market in the late 1970s and early 1980s. Similar to frequency converters, they are also based on electronics and thyristors. It bridges the gap between the functional utility of Star-1 triangle starters and frequency converters, as well as their prices. By controlling the voltage of the motor, it can start smoothly and can also be used for a \"soft\" shutdown ； It boasts advantages such as high reliability, low maintenance requirements, excellent motor protection, and simple parameter setting, thereby fundamentally addressing the many drawbacks of traditional reduced-voltage starting devices. With the rapid development of power electronics technology, AC soft starters have been widely used. 1 Principle of AC soft start (1) A soft starter is a motor control device that combines functions such as soft starting of the motor, soft stopping, energy savings at light loads, and various protection features. Its main components are three-phase parallel thyristors connected in series between the power supply and the motor to be controlled, along with its electronic control circuit… (2) The technical approach adopted by soft starters is thyristor-based AC voltage and speed regulation. To achieve good speed control performance, a dual-loop control system consisting of a speed feedback loop and a current cutoff negative feedback loop is used, with the loop control implemented via PI regulation. (3) In accordance with the requirement of multi-machine, multi-point drive for belt conveyors in coal mines, power balance technology is employed: one soft starter is used as the main unit to control the speed, while the others serve as slave units that monitor changes in the current of the main unit to ensure that the output power remains balanced. Multiple soft starters coordinate their operation through RS485 communication, with a drive distance of up to 1.2 km. (4) The start curve adopts a constant acceleration curve with an ‘s’ characteristic; in order to effectively overcome the static torque during heavy-load starting, the control system can automatically use a ‘jump’ start method depending on the load conditions. 2 Soft start method: A soft starter is used, connected in series between the power supply and the motor to be controlled, to regulate the conduction angle of its internal thyristors. This allows the voltage applied to the motor to increase gradually from zero according to a predefined functional relationship, until the starting process is complete and the motor receives full voltage – this is what is known as soft starting. During the soft start process, the motor’s starting torque gradually increases, and so does its speed. Soft starting generally includes the following starting methods: a fixed low-voltage cable. Electrical design is an important part of the working face design, and it is a crucial element for ensuring safe production in coal mines. Especially for medium and large-scale mines that are severely affected by small coal mines and whose exploitable resources are gradually running out, proper mechanical and electrical design, scientific selection of mechanical and electrical equipment for the working face, and optimization of the layout of such equipment can enable the working face to achieve the best combination of engineering and mechanical/electrical design solutions. This is of great significance for enabling the mine to carry out centralized production in an efficient manner and achieve a high return on investment.